1. Field of the Invention
This invention relates to equine leg and cooling apparatus and method. Specifically, it relates to a boot/elastomeric orthotic pad assembly and method to apply cooling to an equine hoof and leg that is useful for preventive treatment for performance stress and lameness, including laminitis.
2. Background
It is known that cold therapy is helpful in preventing injury in animals before and after stressful activity. As quoted in an article in The Chronicle of the Horse, “Cold therapy is used by every international team at every competition,” said Merrick. “Without a doubt, cold therapy got some of our team horses through. It's called high performance for a reason, and the demands on the horses are high. On the international stage where therapeutic medication is not allowed to help with recovery or minor pain relief, icing is the primary way to maintain the horses' comfort and performance.” Jennifer M. Keeler, Ice Down To Ride On, The Chronicle of the Horse; Sep. 9, 2013 (www.chronofhorse.com). Also see E. R. Hunt, Response of Twenty-seven Horses with Lower leg Injuries to Cold Spa Bath Hydrotherapy: Journal of Equine Veterinary Science; Volume 21, Number 4, 2001, p188-193. The use of seawater and magnesium salts in a cold water therapy is also well known as beneficial in healing and recovery of stress and other injuries.
To address the need for equine cryotherapy there is a number of walk-in Equine Spas commercially available. These are finding wide acceptance by equine veterinary specialist, Veterinary schools (such as the University of Tennessee) and individual performance horse owners. While highly beneficial, these are expensive and not portable. The company CET Equine Spas has introduced a “portable” spa unit that comprises a large refrigeration/circulation unit and a stainless bucket for equine to stand one leg into. www.cet-equine-spa.com.
Cold or cryotherapy is also known to be an effective method of preventing or lessening the effects of laminitis in equines. Equine lameness has many causes, of which laminitis is among the most serious. Laminitis, often called founder, is a disease that affects fifteen (15) percent of the horse population and results in debilitation in nearly seventy-five (75) percent of those horses. Despite recent intensive investigation, no cure currently exists; but early detection and prompt treatment can, in most cases, prevent the need for euthanasia. Laminitis is a fastacting disease that attacks and breaks down the connective tissue, the laminae, between the horse's hoof wall and coffin bone. The disease occurs in three successive stages: the developmental, the acute, and the chronic. The developmental stage of laminitis occurs between initiation of the disease and the appearance of acute lameness which lasts a maximum of seventy-two (72) hours. The acute stage can last between four (4) and sixty (60) hours. This means that many horses may be already in the chronic stage of the disease before they receive treatment. Therefore, until an actual cure is found, a feasible method for preventing and treating the disease is needed. While a cure for laminitis may be developed in the distant future, recent research on the use of cryotherapy (or cold therapy) as a potential prophylactic offers immediate hope for preventing the disease. Two landmark studies from the Australian Equine Laminitis Research Unit have opened this area of research. Pollitt and Van Eps ((Pollitt, C. C. and Van Eps, A. W., Prolonged, continuous distal limb cryotherapy in the horse; Equine Vet. J. 2004; 36(3): 216-220) initially evaluated the effect of prolonged, continuous cryotherapy to the equine distal limb. They found that continuous cryotherapy was well tolerated and resulted in a marked cooling of the treated foot. In a subsequent study, Van Eps and Pollitt determined that distal limb cryotherapy could be used to prevent laminitis induced by alimentary carbohydrate overload. (Van Eps, A. W. and Pollitt, C. C. Equine laminitis: cryotherapy reduces the severity of the acute lesion. Equine Vet. J. 2004; 36(3): 255-260) The results of the Van Eps and Pollitt study suggest that cryotherapy could be used as a potentially effective prophylactic strategy in horses found to be at risk of developing acute laminitis. Even though cryotherapy has been shown to be a potentially effective strategy, the method used, icing down the horse's leg is both cumbersome and imprecise. Furthermore, researchers have previously only used cryotherapy on one leg of the test animals for a short time.
The present invention provides a greatly improved light weight portable apparatus assembly and method for cryotherapy for animals, especially equine animals.